Her younger brother, Kai, who was 14 was one of the youngest to die in the fire.

Tragically, their parents, Jon and Sara Shepherd still have no idea both their children have succumbed to their injuries.

Kressa Jean Shepherd, 17, far right, died Sunday afternoon at a Northern California hospital. Her brother Kai, 14, died during the fire. Parents, Sara and Jon are still recovering unaware that both of their children are dead

Doctors performed a CAT scan on Kressa's brain and to determine she was brain-dead

Kressa, pictured left with her brother, right, had both of her legs amputated below the knee

Speaking about Kressa's death on Sunday night, her aunt, Mindi Ramos, says officials from Shriners Hospital for Children told her Kressa did not register pain during a change of the dressing on her burns.

'We have lost Kressa Jean. Today during a dressing change it was noticed that she was in no pain which is very unusual,' family members wrote on a fundraising page.

'They did a CT scan and it showed that her brain had been dead for some time. There was nothing the doctors could do. She is no longer in any pain and is with Kai now. Please continue to pray for strength to get through the loss of this precious soul. '

In the weeks since the fire, Kressa had both of her legs amputated below the knee because of severe muscle damage.

Doctors performed a CAT scan on her brain and according to Ramos determined she was brain-dead.

She says doctors 'turned off the ventilator and let her go.'

Kressa's brother, 14-year-old Kai Shepherd, was among the youngest who died in the wildfires.

Their parents are are still in hospital. Sara had burns in over 60 percent of her body and is at UC Davis Medical Center, in Sacramento, while Jon was burned over 45 percent of his body and is hospitalized in stable condition at St. Francis Memorial Hospital's burn unit in San Francisco,

She said her sister and brother-in-law are conscious but only talk in whispers and have not asked questions about what happened.

'We don't know how much they remember from that day but we were advised to not give them the tragic news about their children unless they ask,' Ramos said to CBS News.

She said her family is staying strong for her sister.

'Her entire life has been devastated and we're just taking it one breath at a time, one minute at a time,' Ramos said.

Sara, 40, and Jon Shepherd, 44, are in hospital and have gone through several grafting surgeries. Sara had burns in over 60 percent of her body. Jon was burned on over 45 percent

After flames swept over a mountain, the Shepherds had tried to drive down to escape.

Their neighbor Paul Hanssen found their two charred vehicles blocking the road, doors still ajar from when they had apparently abandoned them and fled on foot.

Hanssen found mom, Sara, and Kressa, lying on the ground, with more than half their bodies burned. Kai Shepherd was further down the mountain.

First responders found Kai's father, Jon Shepherd, separately, on the mountain.

Kressa was a junior at Ukiah High School. Both her legs had been amputated and she had never regained consciousness at the hospita. The teen became the 43rd victim of the wildfires

He was also badly burned but alive. Jon reportedly suffered a minor heart attack, but is now in stable condition. He, along with his wife, have already undergone skin graft surgeries.

In addition to their injuries, the family's home was destroyed and it didn't have fire insurance.

Sara's sister started a charity account for the family on Generosity.com, and it has already raised $221,000 to help get Jon and Sara's lives back on track.

Sara's parents lived nearby and their house was spared in the fires.

The plan is to bring the pair back there to recuperate when they are healthy enough to leave the hospital.

Community members have offered to retrofit Sara's parents house.

'We have a huge community of people stepping up to support them,' Ramos said. 'It's really amazing, if there's one thing to be grateful for.'

Ramos remembered Kai as a sweet, brave and compassionate boy who loved the San Francisco Giants and wrestling.

'He could just see into people's hearts, you know?' Ramos said.

A row of chimneys stand in a neighborhood devastated by a wildfire near Santa Rosa. 8,400 homes were destroyed in the fire